Property And Equipment, Net (Tables)

3 Months Ended

Mar. 31, 2017

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment

As of March 31, 2017 and December 31, 2016, total property and equipment, net consisted of the following:

	March 31, 2017			December 31, 2016
	(In thousands)
Oil and gas properties, full cost method
Proved properties		$4,817,044			$4,687,416
Accumulated depreciation, depletion and amortization and impairments	(3,445,709		)	(3,392,749		)
Proved properties, net	1,371,335			1,294,667
Unproved properties, not being amortized
Unevaluated leasehold and seismic costs	221,039			211,067
Capitalized interest	32,231			29,894
Total unproved properties, not being amortized	253,270			240,961
Other property and equipment	23,240			23,127
Accumulated depreciation	(13,641		)	(12,995		)
Other property and equipment, net	9,599			10,132
Total property and equipment, net		$1,634,204			$1,545,760

Schedule of Impairment of Oil and Gas Properties

Details of the 12-Month Average Realized Price of crude oil for the three months ended March 31,2017 and 2016 and the impairment of proved oil and gas properties for the three months ended March 31,2016 are summarized in the table below: 

	Three Months Ended March 31,
	2017			2016
Impairment of proved oil and gas properties (in thousands)		$—		$274,413
Crude Oil 12-Month Average Realized Price ($/Bbl) - Beginning of period	$39.60			$47.24
Crude Oil 12-Month Average Realized Price ($/Bbl) - End of period	$44.98			$43.13
Percentage increase (decrease)	14		%	(9	%)